Spiral stitching device for a sewing machine



March 6, 1962 5. J. TOBIAS ETAL 3,023,719

SPIRAL STITCHING DEVICE FOR A SEWING MACHINE Filed Aug. 26, 1957 2 Sheets-Sheet 1 STEPHEN J. TOBIAS WILLIAM KAUFMAN March 6, 1962 s. J. TOBIAS ETAL SPIRAL STITCHING DEVICE FOR ASEWING MACHINE Filed Aug. 26, 1957 2 Sheets-Sheet 2 2 w: mo. mm l N9 l x n mm ow E. m wv [I I. m .3 NN n E mw u on K mm l l H vw m 8 No a fi 09 mm 1 I E on k w m vm Nm INVENTORS STEPHEN' J. TOBIAS WILLIAM KAUFMAN United States Patent 3,023,719 SPIRAL STITCHING DEVICE FOR A SEWING MACHINE Stephen J. Tobias, 17 Monroe Place, and William Kaufman,575 King St., both of Port Chester, N.Y. Filed Aug. 26, 1957, Ser. No. 680,043 6 Claims. (Cl. 1122) This invention relates to sewing machines and more particularly to a part thereof for producing a spiral seam on a work piece. In particular, the present invention is directed to a mechanism for producing a spiral stitch on brassiere cups as well as on other shaped forms and flat work pieces.

It is an object of the present invention to provide a device which may either be an integral part of a sewing machine or an attachment therefor. If the latter, it may be easily and rapidly afiixed to a conventional commercial sewing machine.

Another object of the present invention is to provide a novel spiral stitching attachment having a manual dial adjustment for operating the clutch of the mechanism after a predetermined travel of the feeder plate. Thus, the sewing machine can be made inoperative automaticah ly upon the completion of a predetermined amount of spiral stitching. The aforesaid manual dial adjustment is easy to operate, and is accessible to the operator without change of position.

A further object of the present invention is the provision of a yieldable chuck resiliently attached to the sewing machine housing and adapted to fit over the workholding needle mounted on the feeder plate. This chuck maintains the work piece in the proper operating position while the spiral stitching is being performed thereon and can be easily and rapidly removed from the workholding needle when changing work pieces.

Another object of the present invention is to provide a work-holding needle which is releasably captured in an opening by means of an elliptical screw-head thus affording rapid, simple and positive replacement of work-holding needles.

Similar to our co-pending application Serial No. 635,- 215 filed January 22, 1957 and now U. S. Patent No. 2,955,551, the present invention is directed to a novel spiral stitching attachment which may be rapidly returned to its starting position after the completion of stitching on the work piece without necessitating any operation except the disengagement of the clutch. Hcretofore, rapid production of brassiere elements was curtailed because many manual operations were necessary before the spiral stitching mechanism was returned to its initial starting position after the completion of stitching of a work piece. The present invention has evolved in order to eliminate these manual manipulations and reduce the operation to its simplest arrangement with all the structure necessary for the spiral stitching of various size brassiere cups.

The above and other features, objects and advantages of the present invention will be fully understood from the following description considered in connection with the accompanying illustrative drawings.

FIG. 1 is a side elevation view of the spiral stitching device embodying our present invention being partly in section and having part thereof omitted for the sake of clarity,

FIG. 2 is a top plan view having part thereof in section, and part thereof removed for purposes of clarity.

Referring more particularly to the drawings wherein is illustrated in dotted lines a conventional commercial sewing machine referred to by the numeral 10. The sewing machine 10 has a reciprocating needle-gripping portion 12. The sewing machine itself, being well-known, forms no part of the present invention.

The spiral stitching device which in this case is illustrated as an attachment to the sewing machine is located below the conventional work table 14. The table 14 is provided with an elongated slot 16 and supports a frame member 18 for the mechanism of the spiral stitching device. Covering the slot 16 in the table is a flat feeder plate 20. This feeder plate 20 moves in the direction of the arrow A during the spiral stitching of the work piece and in the direction of the arrow B on return of the feeder plate to its initial position. As stated before, the operating mechanism is located below the level of the table and may be easily hidden from view by means of a skirt (not shown) at least partially surrounding the frame member 18. Thus, no dangerous, or dirty oil containing mechanisms are located above the level of the work table to injure the operator or soil the merchandise to be stitched.

Mounted at an angle in frame member 18 is a shaft 22 which is secured by means of pivot nuts 24. The angular position of the shaft 22 is desirable for the complete lubrication thereof. Rotatable on shaft 22 is a conical cam 26 which is provided with a continuous helical groove or track 28 which has a predetermined and changing pitch angle. The pitch angle is so chosen that upon operation of the sewing machine 10 a spiral stitching pattern is made on brassiere cup work piece 11 which consists of a continuous series of concentric spirals being preferably equally spaced apart. Incorporated in our mechanism is a device for causing the follower 30 to continually engage the leading edge 29 of track 28 (FIG. 2). This is accomplished by means of a spring 32 which is attached at one end by a screw 34 to the small end of conical cam 26, and the free end thereof is secured to frame member 18. Thus, as the feeder plate 20 is moved to the right in the direction of arrow A as seen in FIG. 1

the spring 32 is tensioned and consequently biases the leading edge 29 of track 28 toward the follower 30. The follower 30 is connected to the feeder plate 20 by means of bridging element 35 (FIG. 2). However, bridging element 35 is connected directly to a sleeve 80, and sleeve is connected by means of plate 81 to a dial 58, all of which will be disclosed more specifically hereinafter.

The spiral stitching device constructed in accordance with the present invention is driven from a motor (not shown) which is operatively connected to drive shaft 36 having a worm 38 thereon. Worm 38 meshes with worm gear 40. The latter in turn meshes with gear 42. Gear 42 is mounted on shaft 22. An helical spring 46 surrounds shaft 22 and has one end engaging face 44 of gear 42 while the other end thereof is affixed to a slidable clutch disc 48. A rotatable shaft 50 is mounted transversely in frame member 18 by means of threaded nuts 52. Preferably close to the center of the shaft 50 is a cut-out portion 54 in which a part of the clutch disc 48 loosely fits. Thus, it should be noted that when shaft 50 is rotated in a counter clockwise direction surface 56 of the cut-out portion 54 engages clutch disc 48 to thereby move the same to the left (FIG. 1) and consequently move the hub 49 of clutch plate 48 out of engagement with clutch face 27 of conical cam 26.

In order to regulate the amount of stitching on each brassiere cup work piece 11 a dial 58 is provided having a pointer 60 and a knob 62. The pointer 60 can be turned to any of the settings A, B, C, or D on plate 64. The settings indicate the type of brassiere cup 11 to be stitched. Naturally, more stitching is required for a. D cup than for an A cup. Knob 62 base shank 66 which is provided with a lateral arm 68. Mounted on arm 68 is a retaining cylinder 70 having an opening 72 therethrough and a set screw 74 for releasably holding one end of a length of wire 76. The other end of wire 76 has an elongated portion 78 which is bent at its extremity. Surrounding a major portion of wire 76 is a sleeve 80.

A specially-shapedleveriarm 82 is mounted on frame member 18 by meansof a pivot 84." Also attached to lever arm 82is a downwardly-directedprojection 86. A spr'ing88 normally maintains projection 86 in engagethem with the left hand surface of arm 90 secured to shaft 50 (FIG; 1) while the device is in operation. The arm' 90 is integrally attached to shaft 50 as more clearly seen in FIG. 1. f Spring 88 is fixed to frame member 18 by means of screw 92.

Mounted on one end of feeder slide 20 is a replaceable needle 96 which is insertable' in relatively large opening 98, the bottom portion of which is screw-threaded. A screw 100 having a relatively large slotted head 102 is non-circular as seenin FIG. 2 and cut away at 104. Thus, by rotating screw 100 in partially threaded opening 98 with the needle 96 engaging the head 102 laterally, the sides of the screw head 102 cam the needle 96 tightly in the opening. To release theneedle 96 the screw 100 need only be rotated a few degrees in the opposite direction and the needle may be easily removed;

In or'derfto hold the brassiere. cup'work piece 11 in the proper stitchingposition a chuck 105 (FIG. 1) having expandable jaws may be easily and rapidly inserted over the needle 96. The chuck 105 is preferably secured to the sewing machine and by means of a spring 106.

A safety release mechanism is shown having a sleeve 108, a collar 109 and a rod 110 movable rectilinearly. Sleeve 108 is provided with 'a hand knob 112, and rod 110 hasa' conical end portion 114. An assembly 116 for operating the safety release mechanism is directly connected to the sewing machine foot pedal (not shown) for activating the safety release mechanism by foot.

It should be noted that when brassiere cup work piece 11 is inserted at its apex over needle 96 for spiral stitching of the brassiere cup the latter is moved in the direction of arrow A by means of feeder plate 20 which is operatively connected to follower 30 riding in thetrack 28 of conical cam 26. Since the clutch is engaged, the conical cam 26 is rotated by the drive means. The stitching of the brassiere cup continues for a distance traversal depen'dingupon the setting of wire 76 in sleeve 80. The enlarged end 78 of'the wire 76 rides along lever arm 82 until it strikes inclined portion 83 of the lever arm 82 causing the latter to pivot about pivot 84 and release arm 90 which is moved in a counterclockwise direction by spring 91 that in turn causes the slidable clutch disc 48 to be moved to the left and out of engagement with clutch face 27 of conical cam 26. Thus, the drive of the conical cam 26'is interrupted. 'In addition, the driving means (not shown) for the reciprocating needle gripping portion 12 of the sewing machine 10 is stopped by means of the rotationof arm 90. The projection 86 then engages the right hand surface of arm 90,'as the latter rotates slightly in a counterclockwise direction. By pulling out rod 112'the conical end portion 114 thereof ensures that the projection 86 engages the right hand surface of arm 90. When it is desired todrive the conical cam 26 again the clutch is engaged by pushing in rod 110 which causes the lever 82 to rotate sufficiently in a clockwise direction so that arm 90 once again resumes a position with the right hand surfacethereof engaging the projection 86 and the clutch engaged due. to the factthat the clutch disc 48 has moved to the right into engagement with the clutch face 27 of the conical cam 26. It should be noted that the follower 30 is attached tothe bridging element 35, the latter being connected directly to the sleeve 80. The sleeve 80 is furthermore connected to plate 81, the latter being connected to dial 58. 7

While we have shown and described the preferred embodiment of our invention, it will be understood that the latter may be embodied otherwise than as herein specifically illustrated or described and t at in the illustrated embodiment certain changes in the details of construction and in the arrangement of parts may be made without departing from the underlying idea or principle of the invention within the scope of the appended claims.

What we claim is: V 7

1. A spiral stitching mechanism for a sewing machine including stitch forming means and a mechanism for feeding work pieces laterally relative to the central axis of said sewing machine comprising a table for said mechanism having a slit-like opening therein, a frame member under said table, a conical cam having a continuous groove'having one wall forming an helical camming surface therein, means mounting said conical cam in saidframe member below the level of said table, a cam follower spring means exerting a force on said cam in a direction substantially at right angles to the central axis of said cam follower whereby the latter continually engages said camming surface of said groove, a feeder plate positioned above the level of said table, means mounting a. work piece on said feeder plate and having said stitchforming means in engagement with said workpiece, a bridging element located in said opening and operatively connecting said feeder plate 'to said cam follower, drive means for rotating said conical cam whereby said'stitchforming means produces a spiralling seam on said work piece, aclutch" directly operable on said cam for selectively connecting'and disconnecting said drive means to said conical cam whereby said drive means operatively moves said feeder plate in one direction, and a pair of interengaging pivoting levers, one of said levers having a part which operatively engages and disengages said clutch, means connected to said feeder plate and engaging a surface of said other lever whereby upona predetermined travel of said feeder plate in one direction said means causes said other lever to pivot thereby disengaging the one of said levers to thereby cause said clutch to be disengaged.

2. A spiral stitching mechanism for a sewing machine including stitch forming means and a mechanism for feeding work pieces laterally relative to the central axis of said sewing machine comprising a table for said mechanism having a slit-like opening therein, a frame member under said table a conical cam having a'continuous groove having one wall forming an helical camming surface therein, means mounting said conical cam in said frame member below the level of said table, a cam follower continually engaging said camming surface of said groove, a feeder plate positioned above the level of said table, means mounting a work piece on said feeder plate and having said stitch-forming means in engagement with said'workpiece, a bridging element located in said opening and operatively connecting said feeder plate to said cam follower, drive means for rotating said conical cam whereby said stitch-forming means produces a spiralling seam on said work piece, a clutch for selectively connecting and disconnecting said drive means to said conical cam whereby said drive means operatively moves said feeder platein one direction, and means to disengage said clutch and thereby said drive means at a predetermined position of the feeder plate to permit the latter to be moved in another. direction, said means including a pivoting lever having a part thereof which operatively engages and disengages said clutch, a shaft, means rotatably mounting said shaft substantially transverse to the longtudinal axis of said conical cam, said shaft being provided with a cut-outportion engaging ,part of said clutch when said shaft is rotated and an upstanding arm, the latter engaging said part of the pivoting lever, and adjustable means causing said pivoting lever to pivot upon a predetermined travel of said feeder plate in one direction to release said upstanding arm and to thereby cause said clutch to be disengaged, said spiral stitching mechanism also including a movable rod mounted in and projecting through said frame member, said rod being provided with a conical end portion in engagement with a part of said pivoting lever, and movement of said rod in a direction substantially perpendicular to said pivoting lever causes said pivoting lever to pivot in a predetermined direction thereby also releasing said upstanding arm and causing said clutch to be disengaged.

3. A spiral stitching mechanism for a sewing machine including stitch forming means and a mechanism for feeding work pieces laterally relative to the central axis of said sewing machine comprising a table for said mechanism having a slit-like opening therein, a frame member under said table, a conical cam having a continuous helical camming surface therein, means mounting said conical cam in said frame member below the level of said table, a cam follower continually engaging said camming surface, a feeder plate positioned above the level of said table, means mounting a work piece on said feeder plate and having said stitch-forming means in engagement with said workpiece, a bridging element located in said opening and operatively connecting said feeder plate to said cam follower, drive means for rotating said conical cam whereby said stitch-forming means produces a spiralling seam on said work piece, a clutch co-acting directly with said cam for selectively connecting and disconnecting said drive means to said conical cam whereby said drive means operatively moves said feeder plate in one direction, and means to disengage said clutch and thereby said drive means at a predetermined position of the feeder plate to permit the latter to be moved in another direction, said means including a pair of pivoting levers, one of said levers having a part thereof which operatively engages and disengages said clutch, and adjustable means causing the other of said pivoting levers to pivot upon a predetermined travel of said feeder plate in one direction, said adjustable means including a wire with an end portion bent out of the plane of said wire and said other pivoting lever having an inclined part whereby when said wire end portion engages said included part in one direction of movement thereof said other pivoting lever pivots to thereby operatively disengage said clutch.

4. A spiral stitching mechanism for a sewing machine including stitch forming means and a mechanism for feeding work pieces laterally relative to the central axis of said sewing machine comprising a table for said mechanism having a slit-like opening therein, a frame member under said table, a conical cam having a continuous groove having one wall forming an helical camming surface therein, means mounting said conical eam in said frame member below the level of said table, a cam follower continually engaging said camming surface of said groove, a feeder plate positioned above the level of said table, means mounting a work piece on said feeder plate and having said stitch-forming means in engagement with said workpiece, a bridging element located in said opening and operatively connecting said feeder plate to said.

cam follower, drive means for rotating said conical cam whereby said stitch-forming means produces a spiralling seam on said work piece, a clutch for selectively connecting and disconnecting said drive means to said conical cam whereby said drive means operatively moves said feeder plate in one direction, and means to disengage said clutch and thereby said drive means at a predetermined position of the feeder plate to permit the latter to be moved manually in another direction, said means including a pair of pivoting levers, one of said levers having a part thereof which operatively engages and disengages said clutch, and adjustable means causing the other of said pivoting levers to pivot upon a predetermined travel of said feeder plate in one direction, a replaceable needle mounted on said feeder plate, an expandable chuck for gripping said needle, and resilient means secured at one end to said sewing machine and at the other to said expandable chuck.

5. A spiral stitching mechanism as set forth in claim 4 wherein said feeder plate is provided with a screwthreaded aperture at one end having a screw therein with a non-circular head portion, said needle being securely mounted in said aperture upon rotation of said noncircular head portion camming said part of said needle into firm engagement with a part of the periphery of said aperture.

6. A spiral stitching mechanism as set forth in claim 3 wherein said means mounting said conical cam below the level of the table is a rotatable shaft having conical end portions positioned angularly relative to the plane of said table, and means in said frame member for retaining said conical end portions.

References Cited in the file of this patent UNITED STATES PATENTS 94,677 Warth Sept. 7, 1869 2,437,624 Sutker Mar. 9, 1948 2,717,566 Szczepanski et a1 Sept. 13, 1955 2,730,974 Ross et a1 Jan. 17, 1956 2,737,133 Desperak et al. Mar. 6, 1956 2,863,407 George Dec. 9, 1958 FOREIGN PATENTS 1,062,620 France Dec. 9, 1953 750,812 Great Britain June 20, 1956, 

